Grinding-machine.



PATENTED J-AN. 13, 1903.

' M. O. KASSON.

GRINDING MACHINE.

APPLICATION FILED MAY 12, 1002.

NO.MODEL.

ihvirnn STATES PATENT OFFICE.

MAHL'ON O. KASSON, OF SANDYHIL L, NEW YORK, ASSIGNOR TO UNION BAG &PAPER'COMPANY, A CORPORATION OF NEW JERSEY.

GRINDING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 718,474, dated January13, 1903.

Application filed May 12, 1902. Serial No. 106,919: (No model.)

To all whom, it may concern.-

Be it known that I, MAHLON O. KASSON, a citizen of the UnitedStates,residing at Sandyhill, New York, have invented certain new anduseful Improvements in Grinding-Machines, of which the following isaclear, full, and exact description.

My invention relates to a fluid-controlled device, and in the presentembodiment I have shown it as applied'to a grinding device, preferablyone adapted for grinding wood-pulp.

My invention will be defined in the claims.

In the drawings, showing the preferred embodiment of my invention,Figure 1 is a side elevation, the greater part of the machine beingshown in central vertical section, and

Fig. 2 is an enlarged section of the rotary valve.

In the above preferred embodiment, 1 is the casing of the machine, inwhich rotates a grinding device, such as a grindston'e2,which is keyedto'adriving-shaft 3.

4c, 5, and 6 are compartments or boxes, open at their ends next thestone, through doors 7, 8, and 9,in which billets of wood may beinserted. This general construction has been used heretofore in the art,and a hydraulic ram has also been provided with a pistonhead in each boXto force the wood against the stone, and when the wood in one of theboxes (as box 4, for example) has been nearly exhausted the hydraulicpump has been used to force the piston in the opposite direction inorder to allow the insertion of a fresh load of wood. As, however, thepump only forces a small quantity of water into the piston-cylinder ateach stroke, it takes a comparatively long time to return the piston toits outer position in this way, and much time has consequently been lostin the use of the machines of the prior art; but in the embodiment of myinvention shown in the drawimgs I have provided a construction whichrelieves the hydraulic pressure on the pistons and returns it quickly toits outer position, thus avoiding the slow outward movement thereof madenecessary in prior machines, and consequently saving much timeandallowing one man to attend to more machines.

In the illustrated preferred embodiment of my machine I have providedthree boxes,

each of which has a follower 10, which is adapted to be independentlyforced toward the stone. Only two of these devices are normally in use,the third being thrown on to prevent the stone from racing when one ofthe other followers is withdrawn in order to insert a fresh supply ofwood. I prefer to employ a fluid-pressu re to force the followersinward, and in the drawings have shown the follower as operated byhydraulic pressure, but I do not limit myself to such a construction.

In the present embodiment of my invention I have provided awater-cylinder 11, in which a head 12 reciprocates, which head may beattached to a piston-rod 13, passing through both ends of the cylinderand carrying the follower 10 on the inner end thereof. The portion ofthe cylinder at either side of the head 12 therefore forms a separatefluid-chamber, and when water is forced into one of these chambers thehead and follower will be moved in one direction or the other. The head12 therefore is virtually a separate head for each chamber and is theequivalent of two independent heads. Iu'thepresent embodiment the twochambers at the opposite sides of the headare formed by a singlecylinder; but by the words a cylinder and a head I do not limit myselfto a construction which has a single cylinder and a single head therein.The device for supplying the fluid-pressure may be a hydraulic pump 14:,and suitable valve devices may be provided to lead the water into thechamber. In the machine illustrated in the drawings I have provided arotary four-way valve 15 for making the desired connections, and thismay be operated by a hand-lever 16. The two positions of the valve areshown in the different figures, and when the valve is in the positionshown in Fig. 2 the water is forced from the pump through port 17 andinto the chamber 22 behind the piston-head 12, forcing the piston andfollower to the left or inward and pressing the Wood against the stone.The chamber 21 at the left of head 12 is in Fig. 2 connected throughport 18 in the valve with a common port 19, from which leads an openwaste-pipe 20. This constitutes one form of a relieving device torelieve the pressure of the water in the chambers and allow it to passaway, and when the valve is thrown to the position shown in Fig. 1 port17 connects chamber 22 with the waste-pipe and relieves the pressuretherein.

In order to return the followerthat is, to move it away from the stone-Ihave provided a construction which, preferably, returns the piston andfollower at a greater rate of speed than it is moved toward the stone.In the present embodiment of my invention this consists of a tank 23,preferably of a considerably greater capacity than that of chamber 21,even when the piston has reached the limit of its movement to the rightor outward. This tank may be located at a point sufficiently higher thanthe machine to give a suitable pressure. I prefer to have this tankair-tight, but to leave a quantity of air in the same. The tank may beconnected by pipe 24: with the rotary valve. It now water is forced intothis tank, it will compress the air therein, and this air pressing onthe surface of the water gives an elastic pressure thereon. I prefer toforce the water into the tank by connecting it with the pump 14 by anopen pipe 25, which is smaller than pipe 26, but large enough tomaintain the necessary pressure in the tank, and while the pump isforcing water directly into chamber 22 and driving the piston toward thestone a small quantity of water is forced into the tank until theair-pressure therein nearly equals the force exerted by the pump. Thetank and air therein therefore constitute one form of an elasticpressure device. The boxes 5 and 6 and their pistons and water-cylindersmay be similarly constructed and cross-connected to tank 23 by pipe 27,as shown, and the similar supplypipe 28 may be connected to pump 14 orto another separate pump, as desired.

If the attendant wishes to reload box 4, he by lever 16 throws the valveof cylinder 29 to the position shown in Fig. 2, thus forcing the pistonof cylinder 29 downward and throws valve 15 to the position shown inFig. 1. This will relieve the pressure in chamber 22 by disconnecting itfrom the pump and connecting it with the waste-port. The valve will alsoconnect the chamber 21 with pipe 24 and the tank, and the air-pressuretherein will suddenly fill said chamber with water under a pressureequal to that of the air in the tank, and this will force the pistonoutward. As the quantity of water in tank 23 is preferably several timesgreater than thatin chamber 21, even when the piston is at the limit ofits outward travel, the column of water in the tank will be onlyslightly reduced in forcing the piston to the end of its throw, andconsequently the air-pressure in the tank will be only very slightlyreduced and will exert, through the column of water in pipe 24, asubstantially constant pressure on head 12 during its entire travel. Asthe air-pressure is comparatively great and there is no resistance tothe outward travel of the piston, except the expulsion of part of thewater in chamber 22, the piston will be forced Outward at a much greaterrate of speed than it would be if pump 14: were directly connected withchamber 21. The water in chamber 22 acts as a buffer and prevents thepiston from coming against the end of the cylinder with a jar.

The upper half of the rotary valve 15 (shown in Fig. 1 of the drawings)obviously constitutes the valve mechanism which is adapted to close thepassage from the chamber 22 of the cylinder and connect the pipe leadingfrom the pump with said chamber, and the lower half of said rotary valvein said figure constitutes a valve mechanism which is adapted to closethe water connection between the tank and the chamber 21 and dischargethe water from this chamber21. lVhile in the present embodiment I haveformed these two valve mechanisms in one piecethat is, out of the singlerotary valve-plug 15it will be obvious that the valves need not beformed in this way, and I do notlimit myself to such a construction.

When the attendant has filled box 4E, he throws off the operation of thepiston in cylinder 29 and throws valve 15 back to the position shown inFig. 2, thus connecting cylinder 21 with the waste-pipe and allowing thepump to again force piston 12 inward.

I am aware that many variations from the embodiment shown in thedrawings may be made without departing from my invention as claimed, andI therefore do not desire to be limited to the construction hereinillustrated and described.

What I claim is-- 1. A grinder, a followeradapted to move toward andaway from the same, a piston-cylinder, a piston-head therein andconnected to said follower to move the same, a pressure device capableof supplying water under pressure, a discharge-exit from said cylinderon one side of said head, valve mechanism adapted to close said exit andconnect said pressure device with said side of said cylinder wherebywater is forced into said cylinder to move said follower inward towardsaid grinder, a closed tank of greater capacity than that part of saidcylinder on the other side of said head when said head is moved outward,a body of water held in said tank under elastic pressure, and a waterconnection therefrom to said cylinderon said other side of said head,andvalve mechanism adapted to close said water connection and discharge thewater from said other side of said cylinder.

2. A grinder,a follower adapted to move toward and away from the same, apiston-cylinder, a piston-head therein and connected to said follower tomove the same, a pressure device capable of supplying water underpressure, a discharge-exit from said cylinder on one side of said head,valve mechanism adapted to close said exit and connect said pressuredevice with said side of said cylinder whereby water is forced into saidcylinder to move said ICC IIO

follower inward toward said grinder, a closed tank of greater capacitythan that part of said cylinder on the other side of said head when saidhead is moved outward, a body of water held in said tank undercompressed air therein, and a water connection therefrom to saidcylinder on said other side of said-head, and valve mechanism adapted toclose said water connection and discharge the water from said other sideof said cylinder.

3. Agrinder, a follower adapted to move toward and away from the same, apiston-cylinder, a piston-head therein and connected to said follower tomove the same, a pressure device capable of supplying water underpressure, a discharge-exit from said cylinder on one side of said head,valve mechanism adapted to close said exit and connect said pressuredevice with said side of said cylinder whereby water is forced into saidcylinder to move said follower inward toward said grinder, a closed tankof greater capacity than that part of said cylinder on the other side ofsaid head when saidhead is moved outward, a body of water held in saidtank under elastic pressure, and a water connection therefrom to'saidcylinder on said other side of said head, valve mechanism adapted toclose said Water connection and discharge the water from said other sideof said cylinder,and a water-passage from said pressure device to saidtank through which Water is forced into said tank against the pressureof the air therein.

4. A grinder, a follower adapted to move toward and away from the same,a piston-cylinder, a piston-head therein and connected to said followerto move the same, a pressure device capable of supplying water underpressure, a discharge-exit fromsaid cylinder on one side of said head,valve mechanism adapted to close said exit and connect said pressuredevice with said side of said cylinder whereby water is forced into saidcylinder to move said follower inward toward said grinder, a closed tankof greater capacity than that part of said cylinder on the other side ofsaid head when said head is moved outward, a body of water held in saidtank under elastic pressure, and a water connection therefrom to saidcylinder on said other side of said head, valve mechanism adapted toclose said water connection and discharge the water from said other sideof said cylinder, and a water-passage from said pressure device to saidtank through which water is forced into said tank against the pressureof the air therein, said Water-passage being normally open and being ofsmaller diameter than that from said tank to said cylinder. t

5. A grinder, a follower adapted to move toward and away from the same,a piston-cylinder, a piston-head therein and connected to said followerto move the same, a pressure device capable of supplying water underpressure, a discharge-exit from said cylinder on one side of said'head,valve mechanism adapted to close said exit and connect said pressuredevice with said side of said cylinder whereby water is forced into saidcylinder to move said follower inward toward said grinder, aclosed tankof greater capacity than that part of said cylinder on the other side ofsaid head when said head is moved outward, abody of Water held in saidtank under elastic pressure, and awater connection therefrom to saidcylinder on said other side of said head, valve mechanism adapted toclose said water connection and discharge the water from said other sideof said cylinder, a second similar cylinder, head, follower and valvemechanism, and similar connections from said pressure device and tank tosaid second valve mechanism, the valve mechanism of said first cylinderbeing operative independently of the valve mechanism of said secondcylinder.

Signed at Sandyhill, New York, this 5th day of May, 1902.

MAHLON O. KASSON. Witnesses:

O. E. R1311), E. A. GETTEN.

